Manufacture of tuluol.



O. B. EVANS.

MANUFACTURE OF TOLUOL. APPLICATION FILED FEB. 24, 1915.

Patented June 12, 1917.

M/VE/VTOR Owen. Ff0d%e Vans WITNESSES.

ITI'OR/VEK UNITED STATES PATENT @lififiIGE.

OWEN BROOKE EVANS, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOR TQ'IHE UNITEDGAS IMPROVEMENT COMPANY, OF PHILADELPHIA, PENNSYLVANIA, A CORPORA- TIONOF PENNSYLVANIA.

MANUFACTURE or TOLUOL.

' Specification of Letters Patent.

Patented June 112, 11917.

Application filed February 24, '1915. Serial No. 10,280.

7 '0 all whom it may concern:

Be it known that I, OWEN BROOKE EVANS, a citizen of the United States,and a resident of Philadelphia, in the county of Philadelphia and Stateof Pennsylvania, have invented certain new and. useful Improve ments inthe Manufacture of Toluol, of which the following is a specification.

The principal object of the present invention is to provide acomparatively inexpensive and efiicient method for manufacturing crudetoluol from naphtha, so that more crude toluol can be recovered than ispresent in the naphtha prior to its treatment. Another object of theinvention is to provide a process for obtaining toluol which can bepractised by means of apparatus which exist in many gas works.

Solvent naphtha 0r crude naphtha or tar naphtha or heavy naphtha, as itis commercially called, is referred to herein as naphtha and it may bedescribed as a complex mixture of compounds largely of the aromaticseries, such for example as benzol, toluol and Xylol and it is one ofthe fractions obtained by the ordinary distillation of so-called lightoil which in its turn is one of the fractions of distillation of gastar, gas drip and like hydro-carbons. Toluol as referred to herein iscommercial or crude toluol which contains some benzol and the like. Thetoluol content of naphtha is about three per cent. and by my inventionthe toluol recovered is increased to about thirteen per cent., whichindicates a chemical breaking down or molecular rearrangement in theprocess.

According to my invention, naphtha is subjected to a high temperature inthe presence of steam or water gas, or a mixture of both, whereby it isconverted into a hydrocarbon gas and into a vapor consisting of toluoland other members of the aromatic series. This vapor is later condensedout of the gas as a drip, from which the toluol can be recovered bydistillation in any of the well known methods.

By Way of illustration, it may be said that when fixed in the presenceof water gas at a temperature of about 1500 F. there will'be producedfrom the naphtha about 20 cubic feet of gas per gallon, having a candlepower of, approximatelyTO. The drip recovered will amount to aboutseventy per cent. of the original naphtha used, and will contain aboutten times the percentage of low boiling compounds such as benzol andtoluol as that present in the untreated naphtha.

In some cases it may be found advisable to fix the naphtha at a hightemperature without admixture with steam or blue gas, subsequentlypurging the apparatus of the contained hydrocarbon vapors by means ofsteam or water gas. In general, however, this method results in theproduction of more lamp-black than when the naphtha is fixed in thepresence of water gas or steam, and, therefore, this method of procedureis but rarely applicable.

The accompanying drawing illustrates partly in side elevation and partlyin section a form of apparatus useful for the practice of the invention.

In the drawing there is illustrated a Water gas set or apparatus formaking water gas. 1, is the generator, 2 the carbureter, 3 the fixingchamber or superheater, 4 a wash box, 5 a cooling coil and 6 a dripreceptacle. 7 are air connections for blasting the generator to makeproducer gas and for burning the producer gas to preheat thecheckerbrick 8. This operation is called the blast and during it theproducts of combustion pass off at 9. 10 are steam connections forintroducing steam through the fire so as to make water gas, whichtraverses the apparatus and can be led away mixed with fixed hydrocarbongases at 11. This operation is called the run. 10 is a connection foradmitting steam to the carbureter. The described steps, that is the blowand the run, are repeated alternately. 12 and 13 are inlets to theinterior of the apparatus.

In the practice of my invention in connection with the describedapparatus the latter is operated in the usual way. However, during theruns naphtha is introduced as by the connection 12 or 13, or otherwisestated, the Water gas is carbureted with naphtha. The associated naphthaand blue water gas traverse the checker-brick, the wash box 4: and thecooler 5, and the carbureted water gas is led off by way of the pipe 11for such use as may be desired. The drip or condensed vapor collected,for example, in the wash box 4 and in the receptacle 6 contains a highpercentage of crude toluol; that condensing in receptacle 6 having ahigher perbustion of producer gas with air, as during the blow, naphthamay be introduced and subjected to its high temperature or fixed withoutthe presence of steam or a mixture of steam and water gas, and in thiscase the apparatus is purged with steam or a mixture of steam and watergas. In general the operation and results in this case are as has beenabove described, except that more lampblack is produced.

What I claim is:

1.- The process of manufacturing toluol which consists inpreheating achecker-brick chamber by internal combustion to a temperaturesufliciently high to materially increase the percentage of toluol,subjecting naphtha of gas drip origin substantially as herein describedto the heat of said chamber thereby forming a gas carrying toluol vapor,leading the gas and toluol vapor from the chamber, and recovering thetoluol, substantially as described.

2. The process of manufacturing toluol which consists in preheating achecker-brick chamber by internal combustion to a temperaturesufliciently high to materially in- ,ingnaphtha of gas drip originsubstantially as herein described to the heat of said chamber therebyforming a gas carrying toluol.

vapor, and recovering the toluol, substantially as described.

4. The process of manufacturing toluol' which consists in heating achamber to a temperature sufficiently high to materially increase thepercentage of toluol, subjecting naphtha of gas drip originsubstantially as herein described in the presence of water gas to theheat of said chamber thereby forming ,a hydro-carbon gas carrying toluolvapor,

leading the gas and toluol vapor from the chamber, and recovering thetoluol, substantially as described.

5. The process of manufacturing toluol which consists in heating naphthaof gas drip origin substantially as herein described to a temperaturesufficiently high to materially increase the percentage of toluoltherein, and recovering the toluol.

OWEN BROOKE EVANS.

Witnesses: I

CLIFFORD K. GAssEL, FRANK E. FRENCH.

